The effect of sandblasting on the retention of first molar orthodontic bands cemented with glass ionomer cement.

This study examined the effect of sandblasting, in vitro, on the bond strength and survival time of first molar orthodontic bands. Survival time was assessed following simulated mechanical fatigue in a ball mill. The amount of cement left attached to the band after debanding was also assessed. In addition, the effect of sandblasting on the failure rate of 320 first molar bands cemented in 107 patients was examined in a half-mouth trial. Ketac-cem, mixed according to manufacturers' instructions was used as the luting agent for both laboratory and clinical trials. In vitro, sandblasting increased bond strength by 27 per cent (P < 0.01) and produced a three-fold increase in the median survival time relative to the untreated sample (P < 0.001) in the ball mill experiment. Sandblasting resulted in more cement remaining on the band rather than on the tooth enamel after band removal. In vivo, sandblasting reduced the clinical failure rate of the first molar bands (P < 0.001).